Endaural phenomena are sounds that are heard without any external acoustic stimulation. Endaural means "in the ear". Phenomena include transient
ringing
Ringing may mean:
Vibrations
* Ringing (signal), unwanted oscillation of a signal, leading to ringing artifacts
* Vibration of a harmonic oscillator
** Bell ringing
* Ringing (telephony), the sound of a telephone bell
* Ringing (medicine), a ring ...
in the ears (that sound like
sine tones),
white noise
In signal processing, white noise is a random signal having equal intensity at different frequencies, giving it a constant power spectral density. The term is used, with this or similar meanings, in many scientific and technical disciplines ...
-like sounds, and subjective
tinnitus
Tinnitus is the perception of sound when no corresponding external sound is present. Nearly everyone experiences a faint "normal tinnitus" in a completely quiet room; but it is of concern only if it is bothersome, interferes with normal hearin ...
. Endaural phenomena need to be distinguished from
otoacoustic emission
An otoacoustic emission (OAE) is a sound that is generated from within the inner ear. Having been predicted by Austrian astrophysicist Thomas Gold in 1948, its existence was first demonstrated experimentally by British physicist David Kemp in 197 ...
s, in which a person's ear emits sounds. The emitter typically cannot hear the sounds made by his or her ear. Endaural phenomena also need to be distinguished from
auditory hallucinations
An auditory hallucination, or paracusia, is a form of hallucination that involves perceiving sounds without auditory stimulus. While experiencing an auditory hallucination, the affected person would hear a sound or sounds which did not come from ...
, which are sometimes associated with
psychosis
Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations, among other features. Additional symptoms are incoherent speech and behavi ...
.
See also
*
Bruit
Bruit, also called vascular murmur, is the abnormal sound generated by turbulent flow of blood in an artery due to either an area of partial obstruction or a localized high rate of blood flow through an unobstructed artery.
The bruit may be hea ...
*
Entoptic phenomenon
Entoptic phenomena () are visual effects whose source is within the human eye itself. (Occasionally, these are called entopic phenomena, which is probably a typographical mistake.)
In Helmholtz's words: "Under suitable conditions light falling o ...
References
Medical terminology
Psychoacoustics
{{ear-disease-stub